.png&w=3840&q=75)
Day Hike Backpack: What Size, Which Pockets and What You Really Need
November 11, 20265 min read
For a hike of a few hours, a 15 to 20 liter backpack is enough. For a full day outdoors, or a hike with kids, go for 25 to 30 liters. Just as important as the volume: side pockets you can grab a bottle from without stopping, a padded back made of breathable fabric, adjustable shoulder straps, and fabric that is water repellent or waterproof.
Products in this guide
Most people shopping for a hiking bag look at the liters first. Then, on the trail, they find the bottle doesn't fit the side pocket, or their back is soaked after half an hour. Here's what to check before you buy, with examples from the backpacks we have in stock right now.
How many liters for a day hike?
The simple rule: how many hours you're out, and how many people the bag carries for.
| Type of hike | Volume | What fits |
|---|---|---|
| Short walk, a one or two hour trail | 9 to 15 liters | Bottle, phone, wallet, hat, a snack |
| Half-day trail | 15 to 20 liters | Two bottles, food, a warm layer, a small kit |
| A full day out, or one bag for the family | 25 to 30 liters | Water for several people, a meal, jackets, a towel |
| A long winter day, or extra gear | 33 to 40 liters | All of the above plus a rain jacket and spare shoes |
In winter the bag fills up faster, because a sweater and a jacket take a lot of room. If you hike in summer and winter, you'll be glad of a bag one size up from what looks right in the store. The full volume breakdown for every use, not just hiking, is in our guide what size backpack do I need.
Pockets: where does the bottle go?
On a hike you reach for your bottle dozens of times. If it's in the main compartment, you stop, take the bag off and open a zipper every time. So the first thing to check is side pockets that hold the bottle you actually carry.
- An elastic side pocket stretches for a thick bottle and still holds it when the bag isn't full.
- A small front pocket for things you grab often: phone, keys, sunscreen.
- One big main compartment is handier than several small ones for food and clothes.
The Nevo Extreme 40L has elastic side pockets for water bottles, and the Peak 33L has side bottle pockets and two outer pockets. Even the small Skippy SV2, at 13 liters, has two side pockets for a bottle or an umbrella.
The back and straps: what you feel after two hours
A 25 liter bag with water and food can weigh several kilos. What decides whether that's comfortable is the side that touches your body. Look for a padded back in breathable fabric or mesh, which keeps a little air between the bag and your back, and padded shoulder straps you can shorten so the bag sits high and doesn't pull you backwards.
On a full, heavy bag, a chest strap keeps the shoulder straps in place and stops the bag swinging on the way down. On a small 10 to 15 liter bag it matters less. The RoamTrek Edge 9L, for example, weighs 310 grams and has a breathable mesh back and padded straps, which is plenty for a short walk.
Rain, dust and wet gear
Water-repellent fabric handles drizzle and light rain; waterproof fabric keeps the contents dry in heavier rain too. For winter hikes or a trail through a stream, a waterproof bag like the Nevo Extreme is the better pick. We explain the difference in water repellent or waterproof, and you can see all bags of that kind on the waterproof backpacks page.
Coming back from a stream with a wet swimsuit or muddy shoes, you'll want a separate compartment. The Drovanis Xtreme 35L has a separate ventilated bottom compartment for shoes or wet gear, and an external attachment system.
The weight of the bag itself
Every gram of the empty bag gets carried for the whole trail. Light day backpacks weigh anywhere from 300 grams to just under a kilo: the Skippy SV2 weighs 300 grams, the RoamTrek Edge 310 grams and the Nevo Extreme 40L 850 grams. A work backpack with a padded laptop compartment and a USB port usually weighs more, so it's a weaker choice for hiking even at the same volume.
Zippers and seams: what breaks first outdoors
On a hike the bag gets dragged over rocks, tossed in the trunk and opened with sandy hands. What fails first is almost always the zipper pull or the seam where the shoulder strap joins the bag. When you choose, look at those two: thick metal zippers or a known zipper brand, and double stitching at the stress points. The Skippy SV2, for example, has #10 metal zippers and double stitching, and the Drovanis Xtreme has YKK zippers.
A short checklist before you buy
- The volume fits your longest hike, not your shortest.
- Your bottle fits the side pocket and comes out without taking the bag off.
- The back is breathable fabric or mesh, and the straps are padded and adjustable.
- The fabric is at least water repellent, and waterproof if you hike in winter.
- The empty weight is listed on the product page, and you know how much it adds.
One bag for the family, or a bag for each kid?
On a family hike, usually one adult carries most of the water and food in a bag of 30 liters or more, and the kids take a small bag of their own with a bottle and a snack. That takes a little weight off the parents too. For a kids' bag, pick one with bottle pockets on both sides, like the WonderWander 17L. We wrote a full packing list for a day trip with kids in how to pack for a day trip.
Want to compare more models? All our backpacks, with volume, weight and stock, are on our backpacks page. Every backpack comes with a 12-month warranty on zippers, straps, seams and manufacturing defects.
Frequently asked questions
Can I hike with a laptop backpack?
You can, especially on a short hike. Just note that a laptop bag usually weighs more than a hiking bag of the same volume because of the padded compartment, and not all of them have side bottle pockets. For regular hikes, a light bag with bottle pockets is the better choice.
Isn't a 40 liter bag too big for a day hike?
For a short hike it's too big and will swing on your back when half empty. It suits a long winter day, one bag that carries the whole family's gear, or someone who uses the same bag for a hike of several days.
What's the difference between a water-repellent and a waterproof bag on a hike?
Water-repellent fabric handles drizzle and light rain; waterproof fabric keeps the contents dry in heavier rain too. For winter hikes or streams, waterproof is better, and either way it's worth putting your phone and documents in a sealed bag.
How do I adjust a backpack so my shoulders don't hurt?
Shorten the shoulder straps until the bag sits high on your back and doesn't hang below your waist. Put heavy things, like water, close to your back. If there's a chest strap, close it at chest height so the straps don't slip.
What size backpack for a child on a hike?
Most kids need only a small bag, around 10 to 17 liters, with a bottle, a snack and a hat. Make sure the bag isn't big or heavy for their body, and that it has a bottle pocket the child can reach alone.
Share this guide
Keep shopping
Our collections related to this guide
